Measurement of Prompt ${D}^{0}$, ${\Lambda }_{c}^{+}$, and ${\Sigma }_{c}^{0,++}\left(2455\right)$ Production in Proton-Proton Collisions at $\sqrt{s}=13\text{}\text{}\mathrm{TeV}$

The ${p}_{T}$-differential production cross sections of prompt ${D}^{0}$, ${\Lambda }_{c}^{+}$, and ${\Sigma }_{c}^{0,++}\left(2455\right)$ charmed hadrons are measured at midrapidity ($|y|<0.5$) in $pp$ collisions at $\sqrt{s}=13\text{}\text{}\mathrm{TeV}$. This is the first measurement of ${\Sigma }_{c}^{0,++}$ production in hadronic collisions. Assuming the same production yield for the three ${\Sigma }_{c}^{0,+,++}$ isospin states, the baryon-to-meson cross section ratios ${\Sigma }_{c}^{0,+,++}/{D}^{0}$ and ${\Lambda }_{c}^{+}/{D}^{0}$ are calculated in the transverse momentum (${p}_{T}$) intervals $2<{p}_{T}<12$ and $1<{p}_{T}<24\text{}\mathrm{GeV}/c$. Values significantly larger than in ${e}^{+}{e}^{-}$ collisions are observed, indicating for the first time that baryon enhancement in hadronic collisions also extends to the ${\Sigma }_{c}$. The feed-down contribution to ${\Lambda }_{c}^{+}$ production from ${\Sigma }_{c}^{0,+,++}$ is also reported and is found to be larger than in ${e}^{+}{e}^{-}$ collisions. The data are compared with predictions from event generators and other phenomenological models, providing a sensitive test of the different charm-hadronization mechanisms implemented in the models.